Method and means for adjusting contacts



April 6, 1948. F. c. GlLL I METHOD AND MEANS FOR ADJUSTING CONTACTS Filed May 17, 1944 1 w M a 0 W 2 k v z @j v y M Patented Apr. 6, 1948 UNITED STATES PATENT QFFICE METHOD AND MEANS FOR ADJUSTING CONTACTS this invention relates to a method and means for adjustment and more particularly to a method and means for adjusting control means for complex machines. A large majority of the machine equipment in our present day factories is automatically controlled, and serious problems of adjustment and correction often arise since many machines have controls incorporating vibrating or rapidly moving parts in order to maintain more accurate or minute control and as such are more difficult to initially set and maintain in the proper adjusted condition. As an example of one of these sets of controls are those which control a so-called profiling machine in which a cutting device is controlled by a tracer or follower engaging a master or template. In order to obtain the proper tolerance for reproduction in this case, vibrating contacts are used which engage stationary adjustable ones, and it has heretofore been difficult to preset the multitude of adjustable contacts in the tracer head under several sets of conditions without the expenditure of a considerable length of time, even by operators who are well acquainted with the equipment. The maladjustment of these contacts also causes dimculty to the operators, for in some instances they believe the difiiculty lies in other parts of the equipment and vary other adjustments in an attempt to locate the trouble and therefore disturb the setting of the Whole machine.

It is therefore an object of my invention to provide a method for accurately and quickly adjusting control contacts.

It is a further object of my invention to provide a method for adjusting control contacts which is rapid, accurate and makes the results readily recognizable by the operator.

It is a still further object of my invention to provide means for indicating correct contact adjustment.

It is a still further object of my invention to provide means which is easily applied and readily removed from the apparatus for normal operation.

With these and other objects in view which will become apparent as the specification proceeds, the embodiments of my invention will be best understood by reference to the following specification and claims and the illustrations in the accompanying drawings, in which:

Figure 1 is a diagrammatic sketch showing my invention as applied 'to the tracer control of a profiling machine.

Figure 2 is an enlarged elevation of the control 2 tracer head with parts being broken away and shown in section.

Figure 3 is a section taken on line 3-3 of Figure 2.

Figure 4 is a schematic wiring diagram of a portion of the circuit.

As previousiy mentioned, a profiling machine is one in which a cutting means develops a contour identical with that of a master over which a tracer or follower passes to duplicate the same contour or part. In order to keep within required tolerances, the controls of these machines are very accurate and particularly in the tracer or follower element must rapidly switch from one direction of feed to another to maintain a relatively smooth reproduced surface at the cutter. In order to obtain as rapid switching as possible, machines have been developed in which a small high-speed motor is used to vibrate the contacts completing the motor control drive circuits for this purpose and of course cooperating with the vibrating or rapidly moving motor-driven contacts are stationary adjustable ones with which they cooperate to close the desired circuits. Inasmuch as it is necessary to have these lattermentioned contacts so accurately set, I have devised a means and a method for rapidly and accurately accomplishing this result.

Referring first to Figure 1, there is shown therein in outline a profiling machine 2 which has a control tracer head indicated generally at 4 which has a iollower arm 6 adapted to contact the master or template 1 and to which are normally attached a series of cables such as 8, l9 and I2 which when the machine is normally operating would conduct control current to the motor to control the direction of feed of the various parts of the machine. However, for adjustment purposes these cables, which normally terminate in a bayonet connection, are withdrawn from the socket in the control head 4 and there is inserted in each of several conductors between the ends thereof and the normal contact in the head an adapter M which also carries a current flow indicator such as, for example, a source of light or bulb It for adjusting the contacts.

The tracer or control head per se is best known in Figure 2 and comprises a casing or housing it which supports a small driving motor 28, the end of whose shaft 22 carries an eccentric driving means 2 3. In the lower surface of the housing there is a threaded opening 26 which carries a long cylindrical hollow member 28 pivotally carrying at its lower end a contact rod This contact rod is embedded in a central force-transmitting member so, itself pivoted about a bulbous enlargement 32 which seats in a mating opening 34 near the lower extremity of the member 28. The upper end of the force-transmitting member 30 carries a cupped member 36 in which seats a transfer member 38 having a contour similar to that of a collar button. Within the upper extremity of the member 28 is a bushing 40, the central opening of which encloses the head of the member 38, said head being adapted to engage the rounded head member 42 of a supporting rod 44 carrying on its upper end a member 36 of insulating material, the uppermost point of which carries a ball bearing pivot 48 for supporting the plate carrying the vibrating contacts. In the means just described, as the follower arm 6 assumes any other position than the vertical, it will tilt the collar button member 38 and thus cause the rising of the support 46--48 to change the relative position of the vibrating contacts with respect to stationary ones.

The contact carrying member shown generally at i! carries a lower bearing race 52 at one end adjacent the eccentric 22 of the motor-driven shaft, and therefore as the motor shaft is driven, will cause the contacts on the opposite side of the pivot 38 to vibrate in a vertical plane. This member 50 carries in insulated relation thereto two sets of contacts: first, contacts 56 and E5; and, second, spaced on the opposite side of the housing, contacts 58 and Gil. The casing I8 has in alignment with vibrating contacts ti t-56, vertical openings 62 and 64 in which are insulatably mounted through sleeves cc and 5S adjustable contact members '10 and 72. Also in the same manner there are provided two screw-threaded adjustable contacts T3 and it which cooperate with vibrating contacts 58 and Bil, respectively. These four sets of contacts control both the longitudinal or main feed and the transverse or follower feed for reproducing the contour, and, specifically, switches 58'M and 60-16 control the longitudinal or main feed drive and contacts 5 4l2 and 56-15 control the transverse or corrective feed.

Under normal operation, therefore, with the tracer arm 5 in its free vertical position, contacts iiil should be closed and contacts 58-'i i should be open, for until the tracer head or rod contacts the pattern or form, it is not necessary to provide longitudinal drive. Likewise for the transverse control, contacts 5tl0 should be in contact, but contacts '5d'i2 should be open. Then as the rod 6 contacts the surface and the transfer post at is deflected from its normally vertical position, the vibrating member 50 will be slightly raised at which time it is desired to cause contacts 5S'i4 to close while contacts lit-i5 still remain closed, completing the circuit for the longitudinal drive and causing the tracer head to move along the surface. At the same time, this rise in position of the support should cause contacts 5d-'i2 to close just as contacts Elli-i6 begin to separate, so that at all times the transverse speed will be moving slightly in one direction or the other.

This may be better explained by reference to Figure 4 in which the duplicating control is shown diagrammatically at 13, the voltage supply at Bil, the small driving motor 26 is shown in the line, and the two vibrating yokes carrying contacts 585@ and 5d56 shown one above the other. The stationary contacts l4'i6 and 'i2-T0 are shown cooperating with their respective paired contacts. Line 32 is shown connecting contacts iii with the duplicator, line 85 connects contact with the same, and line at also connects contact it therewith. From the voltage supply, line 88 extends to contacts 5456 and line 90 to contact 14. It will thus be evident that the previously described closures will control the circuits as disclosed.

In order now to properly set the adjustable contacts l0 and 12, and 14 and 16, the bayonet connection 92 on line 82 and 94 on 86 are pulled from their associated sockets and there is inserted in each line an adapter [4 which has a bayonet projector on one end for insertion into the socket in the control head 4 and a socket connection on the opposite side for the insertion of the bayonet 92 or 95.. Into these adapters are screwed small light bulbs to indicate the flow of current. Any other type of current flow indicator may be used if desired. The motor 29 is now energized and the control head is supported so that the tracer rod 5 asumes its free vertical position. Adjustable contact lt is now brought up until it contacts vibrating contact 56. Contact 14 is adjusted downwardly until it is just out of contact with its associated contact 58 as indicated by the light it in line 82 being dark. The tracer rod 6 is then pulled slightly or defiected to one side and if necessary contact 14 is then further adjusted so that it will make contact with its vibrating contact 58 and at the same time contact 16 will still be in contact with its associated contact to and the lamp it in line 82 will glow brightly. When the arm 6 is again allowed to assume its vertical position, this lamp should go out.

At the same time contact ll! is so adjusted as to be in contact with contact 56 when rod 6 is in its free vertical position, which can be easily determined by the energization of lamp I6 in line 86. However, when the rod 6 is deflected, this lamp should begin to dim and increase dimming until at some exaggerated deflection it will go out entirely, showing a breaking of this contact. In order to adjust contact 12, the fixture i l may be taken out of line 82 and placed in line 8%, and with the same procedure, when the rod t is in free vertical position, contact 12 should not make contact with contact 54 and the lamp should be out, but as the same is deflected these two should engage, and the greater the deflection the more permanent the engagement and the brighter this lamp should glow.

It will therefore be seen that not only can I determine when the vibrating contacts are engaging the adjustable ones, but also the degree of pressure exerted between them, and in this manner accurately and swiftly adjust the various adjustable contacts for control use.

I claim:

1. In control means, a casing, a plurality of contacts adjustably mounted in the casing, a plurality of vibratory contacts vibrated at high frequency whose position within the casing may be altered cooperating with the adjustable contacts, control circuits connected thereto, lamps connected into the control circuits to indicate the degree of contact between the adjustable and vibratory contacts by equal illumination at re duced brilliance of said lamps.

2. In a method for adjusting a plurality of control contacts in a tracer head for a profiling machine whose follower arm varies the position of rapidly vibrating contacts that cooperate with the control contacts to control the machine, the steps of inserting in the control circuit lamps to indicate the flow of current therethrough, adjustin a portion of the contacts until a portion of the lamps are fully illuminated with the follower arm in neutral position, moving the follower arm to a displaced position and adjusting the remainder of the contacts until the remainder of the lamps are illuminated equally at approximately one-half full brilliance, said adjustment being of such degree that the transition from neutral to displaced position of the follower causes the first illuminated lamps to dim and the second mentioned lamps to gradually brighten to full brilliance at the maximum displacement and the first to be extinguished.

3. The method of adjusting the clearances between each of two alternately closed stationary contacts and its mating movable contact on a common oscillating circuit member, including placing efiective current indicating devices oi similar characteristics in each of the stationary contact circuits, vibrating the said oscillating circuit member, integrating the output from each of said circuits, and adjusting the clearances between said movable and said stationary contacts for equal integrated output from each of the current responsive means.

4. The method of adjusting the clearance between each of two alternately closed stationary contacts and its mating movable contact on a common vibrating circuit member, including placing electric lamps in each of the stationary contact circuits, vibrating the said vibrating circuit member at a high frequency, and adjusting the clearances between said movable and said stationary contacts for equal illumination of said lamps.

FRANKLIN C. GILL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Certificate of Correction Patent No. 2,439,362.

FRANKLIN C. GILL It is hereby certified that errors appear in the printed s numbered patent requiring cOIrectiOn reed shown; column 4, line 72, Letters Patent should be read conform to the record of the case in the Patent Signed and sealed this 8th [SEAL] as follows: Column claim 2, for circuit read 02' April 6, 1948.

pecification of the above 2, line 47, for known waits; and that the said with these corrections therein that the some may Oflice. day of June, A. D. 1948.

THOMAS F. MURPHY,

Assistant Commissioner of Patents.

Certificate of Correction Patent No. 2,439,362. April 6, 1948.

FRANKLIN C. GILL It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows: Column 2, line 47, for known read shown; column 4, line 72, claim 2, for circuit read circuits; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 8th day of June, A. D. 1948.

[SEAL] THOMAS F. MURPHY,

Assistant C'ommz'ssioner of Patents. 

